display default font in use

[Harry Putnam]

>From what I saw while trying to find the answer to this ... the usage
of the term default-font, as in set-default-font, is now obsolete and
being replaced (eventually) by default-frame as in `set frame-font

But I hoped to find out how to display what the current default font
is so I used C-h f <RET> set-frame-font <RET> and found some
information that seems wrong, but its likely I don't really understand
what it is saying.

in part:
To get the frame's current default font, use `frame-parameters'.

I tried what that appears to be saying by evaluating:

Shift-Alt-: :(frame-parameters) <RET>

It shows quite a pile of information but none of it appears to be
about the default font.

Here is an example:

((parent-id . 18986016) (explicit-name) (display

. ":0.0") (visibility . t) (icon-name) (outer-window-id
. "44040218") (window-id . "44040220") (top . 552) (left
. 1032) (buried-buffer-list) (buffer-list #<buffer *scratch*>
#<buffer *Minibuf-1*>) (unsplittable) ...)